The 'butt slam' is a pretty standard play move, always funny and they all seem to do it. Nicky does that stop-action mid-lick pause too, but none of the others do.
Nicky has started using the bed-skirts or blankets to wipe her face after eating (how messy can kibble be?) and will go up and down the bed, or sometimes couch, rubbing her face. If I use any kind of smelly spritz int he bathroom, they will all three writhe on the rug.
Nicky's strangest quirk involves eating. Sometimes she will approach her bowl cautiously as if there might be a monster in it, or she will be eating and suddenly back away from it, 2 or 3 rapid steps backward, and I will have to call her and coax her to finish. She may do this several times one day, then not do it again for awhile. We think in her former life there may have been food issues that are residual, because no one here has ever argued with her over food.
The boys don't have many quirks!